In 1991, titanium-diffused blue sapphires reappeared in the Bangkok market after an absence of many years. Touted as “deep diffusion,” the stones proved to have no greater color penetration than the original Union Carbide product.
What does diffused sapphire mean?
Blue diffusion-treated sapphires are be- coming more prevalent than ever before. The diffusion technique, which involves the addition of color-causing chemicnls during heat trentment, results in a thin layer of color at the surface of colorless or light-colored sapphire.
Are diffused sapphires valuable?
Sapphires treated by lattice diffusion generally cost less than sapphires that have been treated by heat without the addition of color-causing chemicals or sapphires that have not been treated.
What is a diffused gem?
Coloured gemstones have undergone treatment for thousands of years. … Diffusion is a technique whereby certain natural elements, those used in nature when colouring allochromatic gems, are placed on the surface of the gem during the heating process and the colour is diffused into the gem.
What is diffused stone treatment?
Lattice diffusion is a treatment process that uses heat and chemicals to diffuse an element into a gemstone to artificially change its color. Lattice diffusion–treated sapphires can be any color. In some cases the added color is shallow. In others, it goes all the way through the stone.
Is Blue Sapphire valuable?
Sapphires can come as cheap as $25 per carat, to over $11,000 per carat. A blue sapphire around 1 carat is likely to cost from as little as $450 to $1,600, depending on quality.
How can I tell if my sapphire is real?
The Fog Test
If you’re looking at a sapphire and want to confirm it’s authenticity, just breath on it for a second. On real sapphires, the fog from your breath will evaporate very quickly (~2 seconds). If it’s fake, it may take 5 seconds or more to start evaporating and 2-3 seconds to actually evaporate.
How do you tell if a sapphire has been heat treated?
The study of inclusions in sapphires is a sure way to detect if a sapphire has been treated. Heating sapphires at extreme temperatures change the internal characteristics so much that it is quite easy for a trained gemologist to determine if the sapphire has been heated.
Are natural sapphires valuable?
Sapphires are the most valuable and rarest blue colored natural gemstones. They are a highly desirable gemstone due to their beautiful royal blue color, hardness (second only to diamonds), durability, and luster (sparkle from light performance within the gemstone).
What is an untreated sapphire?
The key term is “untreated,” meaning a sapphire is natural (not lab created) and has not been subject to any chemical or heat treatments. … Natural untreated sapphires are far more uncommon and valuable than treated and chemically altered stones.
What is Emerald diffused?
Diffusion is a process where gems are heated and an external element or elements are “diffused” into the host gem material. This treatment is less accepted in the market because an external “ingredient” or “ingredients” are introduced into the gem to change its color.
What does flux healed mean?
Flux healing involves heating corundums with borax or other fluxes. These fluxes actually dissolve the surfaces, including the internal surfaces of cracks. The corundum within this molten material then re-deposits on the fracture surfaces, filling and healing the fractures shut.
What makes a sapphire a padparadscha?
When heated to extreme temperatures in the presence of beryllium, poorly colored pink sapphires can emerge with an exquisite pinkish-orange to orangish-pink “padparadscha” color. Beryllium penetrates deep into the sapphire, making it extremely difficult to detect.
What is diffusion with beryllium?
Beryllium diffusion typically brightens the color of ruby or sapphire, making a stone more yellow, orange, or red, depending on the original color.
How can synthetic corundum be distinguished from natural corundum?
Synthetic corundum has distinguishing characteristics. The Verneuil process always produces curved growth lines, which are visible under magnification and with the correct illumination. No natural mineral ever displays such curved lines, called striae, and their presence is a guarantee of synthetic origin.